AIRFIELD VEHICLE MONITORING SYSTEM AND RELATIVE VEHICLE
TECHNICAL FIELD The present invention relates to an airfield vehicle monitoring system and relative vehicle .
BACKGROUND ART
As is known, the safety of passengers and personnel on airfields, particularly in fog, is a major source of concern and the object of continual improvement.
Despite numerous efforts over the past few years to further improve the safety of passenger and personnel traffic on airfields, considerable room for improvement still remains. DISCLOSURE OF INVENTION
It is an object of the present invention to provide an airfield vehicle monitoring system and relative vehicle, designed to further improve safety on airfields.
According to the present invention, there is provided an airfield vehicle monitoring system, as claimed in Claim 1.
BRIEF DESCRIPTION OF THE DRAWINGS
Two preferred, non-limiting embodiments of the
present invention will be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a block diagram of a monitoring system in accordance with a first embodiment of the present invention;
Figure 2 shows a block diagram of a monitoring system in accordance with a second embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION According to a first aspect of the present invention, the airfield vehicle monitoring system basically comprises three subsystems or operating sections: a number of remote or peripheral stations, each installed on a respective monitored vehicle, which may be a safety vehicle (snow plough, follow-me, etc.), or a logistic (aircraft provisioning, refuelling ......) vehicle; a fixed central monitoring station communicating with the remote stations to monitor the relative vehicles; and a mobile central monitoring station identical with the fixed central monitoring station but installed on a dedicated vehicle .
Figure 1 shows a block diagram of a monitoring system in accordance with a first embodiment of the present invention. More specifically, Figure 1 shows block diagrams of one of the remote stations installed on one of the monitored vehicles, and of the fixed and mobile central monitoring stations .
More specifically, in Figure 1, number 1 indicates
the monitoring system as a whole; 2 the remote station; 3 the vehicle equipped with remote station 2 ; and 4 the fixed and mobile central monitoring stations.
As shown in Figure 1, each remote station 2 substantially comprises a GPS (Global Positioning System) receiver 5 having a GPS antenna 6 and cooperating with a GPS system to determine the absolute position (longitude and latitude) of vehicle 3 on the earth's surface, together with other movement parameters of vehicle 3, such as travelling speed, travelling direction, etc.; and a communication device 7 connected to GPS receiver 5 to transmit the position and movement data of vehicle 3 to fixed and mobile central monitoring stations 4, and to receive differential correction data transmitted by one of the fixed or mobile central monitoring stations 4, as explained later on.
More specifically, communication device 7 substantially comprises a mode 8 connected to GPS receiver 5; a UHF radio transmitter-receiver 9 having a UHF antenna 10 and connected to modem 8; and a central processing unit (CPU) 11 connected to GPS receiver 5, to modem 8, and to UHF radio transmitter-receiver 9, and having data transmission-receiving software.
As is known, the GPS system comprises a number of satellites in stationary orbit around the earth, distributed in six different stationary orbit planes, and producing radio signals which are picked up by GPS receivers to determine the position of the receiver to
within roughly one metre. More specifically, given its own distance with respect to at least four satellites, a GPS system receiver determines its absolute position by geometrical triangulation. Fixed and mobile central monitoring stations 4 each substantially comprise a GPS differential correction section (GPSBS) 12 having a GPS antenna 13 and cooperating with the GPS system to supply differential correction data, e.g. in RTCM SC-104 format, which is transmitted to remote stations 2 to precision-enhance the absolute position data supplied by them; and a communication device 14 connected to GPS differential correction section 12 to transmit differential correction data to remote stations 2, and to receive position and movement data of relative vehicles 3 transmitted by remote stations 2.
More specifically, communication device 14 substantially comprises a modem 15 connected to GPS differential correction section 12; a UHF radio transmitter-receiver 16 having a UHF antenna 17 and connected to modem 15; and a central processing unit (CPU) 18 connected to GPS differential correction section 12, to modem 15, and to UHF radio transmitter-receiver 16, and having data transmission-receiving software. Fixed and mobile central monitoring stations 4 each comprise a personal computer 19 connected to GPS differential correction section 12 and to communication device 14, and having software for displaying data
transmitted by individual remote stations.
In actual use, each remote station 2 determines the coordinates (latitude and longitude) of the position of vehicle 3 on which it is installed, and, on the basis of differential correction data transmitted by fixed or mobile central monitoring station 4, precision-enhances the vehicle position data to within roughly 0.5 cm.
Which of fixed and mobile central monitoring stations 4 transmits differential correction data to remote stations 2 is selected on a priority basis, depending on the requirements of individual airfields .
The precision-enhanced position data, together with other movement data of vehicles 3, is then transmitted by respective remote stations 2 to fixed and mobile central monitoring stations 4, where it is displayed on a map on respective personal computers 19.
More specifically, personal computers 19 at fixed and mobile central monitoring stations 4 display a map of the pertinent area, location of fixed and mobile central monitoring stations 4, and location of the various remote stations 2, and therefore of vehicles 3 on which they are installed.
By means of curtain menus, personal computers 19 at fixed and mobile central monitoring stations 4 can display, for each remote station, movement data of vehicle 3 and remote station data, such as travelling direction, latitude and longitude, user identification, travelling speed, the distance between fixed and mobile
central monitoring stations 4 and remote station 2, and the identification numbers of the four satellites used by GPS receiver 5 to calculate the absolute position of remote station 2. According to a further aspect of the present invention, a particular category of airfield safety vehicles 3, known as "follow-me", is equipped with a remote station, which, in addition to the above relative to remote station 2, also comprises an on-vehicle radar, fitted to the vehicle roof, and an on-vehicle screen, inside the passenger compartment, both connected to central processing unit 11.
Figure 2 shows a block diagram of this alternative embodiment of the monitoring system according to the present invention, in which parts similar to those of monitoring system 1 in Figure 1 are indicated using the same reference numbers. More specifically, number 1' in Figure 2 indicates the monitoring system as a whole; 2 ' the remote station installed on a follow-me; 3' the follow-me; 20 the on-vehicle radar; and 21 the on-vehicle screen.
More specifically, vehicles in this particular category are used in fog to escort incoming aircraft from the runway to the parking apron, and outgoing aircraft from the parking apron to the runway, and are so-called by carrying a lighted wfollow-me" sign.
In fog conditions, in fact, airport safety regulations require that incoming aircraft, on landing,
should stop along the runway, and that a follow-me 3' should move up to within a few metres of the aircraft and, after turning on the lighted "follow-me" sign, should escort the aircraft to the parking apron, and likewise should escort outgoing aircraft up to the start of the runway.
Equipping vehicles of this sort with an on-vehicle radar 20 and on-vehicle screen 21 provides, in fog conditions, for safeguarding against collisions between aircraft, or between aircraft and any other vehicle 3 or follow-me 3' circulating on the airfield, in the event of error on the part of a pilot or a driver of a vehicle 3 or follow-me 3 ' .
In fact, though personal computers 19 at fixed and mobile central monitoring stations 4 display the precise position and travelling direction of follow-me's 3' escorting aircraft to and from the parking apron, they do not display the actual aircraft being escorted.
Consequently, in the event of pilot error, when being escorted to and from the parking apron, resulting in the aircraft taking a different route from the relative follow-me 3', airfield vehicle position control personnel, assuming the aircraft is following the follow- me 3' displayed on the computer screens, may authorize takeoff or landing of other aircraft, or movements of other vehicles on the airfield, which may cross the path of the stray aircraft, with obvious consequences.
The special equipment on follow-me 3 ' , on the other
hand, prevents this from happening. That is, the on- vehicle radar 20 determines the precise position of the aircraft, both as follow-me 3' approaches the aircraft, and as the aircraft is escorted to and from the parking apron.
The aircraft's position is then displayed on a map on on-vehicle screen 21 of follow-me 3', together with the position of follow-me 3' itself (and possibly also the positions of any other follow-me' s 3' and of fixed and mobile central monitoring stations 4) .
The aircraft's position and that of the relative follow-me 3' are then transmitted to fixed and mobile central monitoring stations 4 over UHF radio transmitter- receiver 9 of the relative remote station 2', so that both the driver of follow-me 3' and the fixed and mobile central monitoring stations 4 can keep real-time track of the aircraft being escorted to or from the parking apron.
The advantages of the present invention will be clear from the foregoing description. In particular, the present invention significantly improves airfield safety in thick fog, by real-time monitoring, in any weather conditions, not only all the vehicles circulating on the airfield, but also, by equipping each follow-me with an on-vehicle radar, the aircraft being escorted to and from the parking apron, thus enabling immediate intervention by safety personnel in the event of a potential hazard situation.
Moreover, equipping each follow-me with an on-
vehicle radar and screen greatly simplifies approach of the follow-me to the aircraft to be escorted to or from the parking apron, by enabling the approach procedure to be fully instrument-controlled by the driver in thick fog.
Clearly, changes may be made to the monitoring systems as described and illustrated herein without, however, departing from the scope of the present invention as defined in the accompanying Claims . For example, though only referred to in connection with follow-me vehicles, other types of vehicles may also be equipped with an on-vehicle radar and screen. Similarly, a GPS receiver may obviously be provided only vehicles of a certain type, as opposed to all airfield vehicles.
The fixed and mobile central monitoring stations and the remote stations may communicate over suitable airfield systems other than the one described, e.g. one conveniently employing a LAN (Local Area Network) . Airfield vehicle position and movement parameters may be determined using position systems other than the one described, e.g. local position systems.
The monitoring system according to the present invention may also be used in small airports with only one follow-me; in which case, in addition to a fixed central monitoring station and/or a mobile central monitoring station, the monitoring system would comprise one remote station on the one follow-me provided.
Depending on requirements, the monitoring system according to the present invention may even comprise only one fixed or mobile central monitoring station.